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A cellular-enabled Apple Watch allows you to use several features without having your iPhone nearby, which can come in handy during outdoor activities where carrying around an iPhone can be cumbersome (like during a run) or risky (on a boat).

An Apple Watch with a cellular connection and without an iPhone nearby has the same capabilities as an Apple Watch connected to Wi-Fi, including sending and receiving messages and phone calls, streaming music and podcasts, and checking the weather.